diff --git a/xCAT-server/lib/xcat/plugins/ddns.pm b/xCAT-server/lib/xcat/plugins/ddns.pm
index 18bd3f6e9..3b1d8df69 100644
--- a/xCAT-server/lib/xcat/plugins/ddns.pm
+++ b/xCAT-server/lib/xcat/plugins/ddns.pm
@@ -213,6 +213,7 @@ sub process_request {
     if ($help)
     {
         makedns_usage($callback);
+        return;
     }
     
     $ctx->{deletemode}=$deletemode;